Reactivity of effluent organic matter (EfOM) with hydroxyl radical as a function of molecular weight.
Enviado por Fernando Rosario-Ortiz el
Título | Reactivity of effluent organic matter (EfOM) with hydroxyl radical as a function of molecular weight. |
Publication Type | Journal Article |
Year of Publication | 2010 |
Autores | Dong, MMei, Mezyk, SP, Rosario-Ortiz, FL |
Journal | Environ Sci Technol |
Volume | 44 |
Issue | 15 |
Pagination | 5714-20 |
Date Published | 2010 Aug 1 |
ISSN | 1520-5851 |
Palabras clave | Chemical Fractionation, Hydroxyl Radical, Molecular Weight, Organic Chemicals, Oxidation-Reduction, Particulate Matter, Ultrafiltration, Waste Disposal, Fluid, Water, Water Pollutants, Chemical |
Abstract | The application of advanced oxidation processes (AOPs) for the treatment of wastewater is hindered by scavenging of the hydroxyl radical (HO*) by effluent organic matter (EfOM). This scavenging is directly proportional to the second-order reaction rate constant between EfOM and HO* (kEfOM-HO*). To understand the kinetics of this reaction as a function of the subcomponents of EfOM, four wastewater samples were fractionated by ultrafiltration into distinct apparent molecular weight (AMW) fractions (<1, <3, <5, and <10 kDa), and their kEfOM-HO* values were quantified. In general, the values for k(EfOM-HO*) decreased as the AMW increased. The values of k(EfOM-HO*) for the bulk waters varied between 6.32 and 14.1x10(8) MC(-1)s(-1) (units of per molar carbon concentration per second). In the case of the <1 kDa fraction, the values of kEfOM-HO* varied from 14.3 to 35.0x10(8) MC(-1)s(-1), or approximately 2.31(+/-0.24) times that of the corresponding bulk waters. For the <3 kDa, <5 kDa, and <10 kDa fractions, the k(EfOM-HO*) values were 1.83(+/-0.25), 1.32(+/-0.23), and 1.26(+/-0.35) times that of the bulk waters, respectively. Based on the obtained results, the variability and general magnitude of the kEfOM-HO* values were attributed to the production and reactivity of soluble microbial products (SMP), a major component of EfOM. Two samples collected at a wastewater treatment facility with different treatment variables had different kEfOM-HO* values, indicating that wastewater treatment processes will impact overall HO* scavenging by EfOM and should be considered during the implementation of AOPs. |
DOI | 10.1021/es1004736 |
Alternate Journal | Environ. Sci. Technol. |
PubMed ID | 20608709 |